NA Conversion Adapter

The 735383-A001 and A002 are unique adapters that reduces the numerical aperture (NA) of a connected fiber to half and is only applicable to the free space optical input structure on the Yokogawa AQ6370 series optical spectrum analyzers

Unique adapter for the Yokogawa free space input

How It Works

The NA Conversion Adapter halves the numerical aperture (NA) of a connected fiber.

Benefits of the NA Conversion Adapter

Better dynamic range (SNR) for passive component testing

The use of a multimode fiber causes a high coupling loss with a broadband light source so that high output power cannot be expected, and the direct output of such a fiber is reduced in the Monochromator due to the NA restriction.
By attaching the adapter to the end of a multimode fiber, the optical spectral level of a broad band source increases about 5 dB on the OSA.

Better level stability for active device testing

With the direct output of multimode fiber, there are cases where the measured power level becomes unstable due to dynamic speckle noise caused by modal interference.
The NA conversion adapter can resolve the above issue and improves the level measurement stability by efficiently coupling the output beam with the Monochromator.

• Level Fluctuation

• Ripple on LED Spectrum

DFB-LD Spectrum (GI 50/125 µm)

EE-LED Spectrum (GI 50/125 µm)

Product Code

735383-A001

735383-A002

Applicable Fiber

SMF, GI50/125um

SMF, GI50/125um, GI62.5/125um

Wavelength Range

350 to 1700nm (typ.)

NA Conversion Ratio

Approx. 1/2

Applicable OSA Models

AQ6370 series Optical Spectrum Analyzers
Note: the wavelength restriction applies to the AQ6375